Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch bite-sized cubes and slice the red bell pepper into thin strips.
In a large mixing bowl, combine the chicken cubes, broccoli florets, and bell pepper strips.
Drizzle the extra virgin olive oil over the chicken and vegetables, then sprinkle with dried rosemary, garlic powder, sea salt, and black pepper.
Toss everything thoroughly until the chicken and produce are evenly coated in the oil and spices.
Spread the mixture in a single layer on the prepared baking sheet, ensuring nothing is overcrowded so it roasts rather than steams.
Roast in the oven for 18-20 minutes, or until the chicken is cooked through and the vegetables are tender and slightly charred.
While the chicken roasts, warm the pre-cooked quinoa in a small pan or microwave.
Serve the roasted chicken and vegetables over the bed of fluffy quinoa and enjoy immediately.